Abstract:

For an apparatus determining whether or not an HDD is started by
barometric pressure information or the like, there are provided a
navigation apparatus, an operation control device, an operation control
method, and an operation control program, that enable shortening of a
time from a power-on to starting-up of the HDD.
The present application is the operation control device which controls the
operation of the HDD by giving an instruction to the HDD to control the
operation of the HDD, the operation control device including: a recording
means for recording a previous closing information indicative of whether
or not the operation of the operation control device normally ends by a
previous power-off and an operation control means for giving an
instruction of starting the operation to the HDD in a case where the
operation has been normally ended at a time of starting the operation
control device by the power-on.

Claims:

1. An operation control apparatus controlling an operation of a magnetic
disc device having a magnetic disc and a magnetic head for writing or
reading information in or out the magnetic disc while moving over the
magnetic disc without being in contact with the magnetic disc by giving
an instruction to the magnetic disc device, the magnetic disc device
being provided with a guarantee range of assuring reliability of
operation with respect to a state of barometric pressure comprising:a
recording device that recodes a previous closing information indicative
of whether or not the operation control apparatus ends by the previous
power-off under a state of normal barometric pressure within the
guarantee range of assuring operation of the magnetic disc device; andan
operation control device that gives the operation start instruction to
the magnetic disc device in a case where the operation ends under the
normal barometric pressure, irrespective of a state of a barometric
pressure at a time of power-on, in reference of the previous closing
information thus recorded at a time of starting the operation of the
operation control apparatus by power-on.

2. The operation control apparatus according to claim 1, whereinthe
operation control device acquires barometric pressure information
indicative of a barometric pressure at a current position in a case where
the operation did not end under the state of the normal barometric
pressure, and gives an operation start instruction with respect to the
magnetic disc device in a case where the barometric pressure indicated by
the barometric pressure information thus acquired is the normal
barometric pressure.

3. The operation control device according to claim 1, whereinthe operation
control device gives an operation start instruction to the magnetic disc
device and thereafter acquires barometric pressure information indicative
of the current position, andin a case where the barometric pressure
information thus acquired is not the normal barometric pressure, an
operation stop instruction is given to the magnetic disc device.

4. The operation control apparatus according to claim 1, whereinthe
operation control device acquires barometric pressure information
indicative of the barometric pressure at the current position after
giving the operation start instruction to the magnetic disc device, andin
a case where the barometric pressure indicated by the barometric pressure
information thus acquired is a barometric pressure showing abnormality of
a detection apparatus for detecting the current position, the magnetic
disc device continues operation without the operation stop instruction
when the barometric pressure acquired immediately before acquiring the
barometric pressure is normal.

5. The operation control apparatus according to claim 1, whereinthe record
device records the previous closing information indicating that the
operation end is carried out in a state of the normal barometric pressure
in a case where the current barometric pressure is a normal pressure at a
time of ending the operation by power-off.

6. A navigation apparatus having the magnetic disc device and the
operation control apparatus according to claim 1, whereinthe magnetic
disc records navigation data necessary for navigation process including a
route guide process for guiding a route to a destination, andthe
operation control apparatus carries out the navigation process using the
navigation data.

7. An operation control method controlling operation of the magnetic disc
device, that is provided with a guarantee range of assuring reliability
of operation with respect to a state of barometric pressure, by giving an
instruction to a magnetic disc device having a magnetic disc and a
magnetic head for writing and reading information to or from the magnetic
disc while moving over the magnetic disc without being in contact with
the magnetic disc, comprising:a step of recording previous closing
information indicative of whether or not operation end of the operation
control apparatus by a previous power-off is under a state of a normal
barometric pressure within the guarantee range of assuring operation of
the magnetic disc device; anda step of giving an operation start
instruction with respect to the magnetic disc device irrespective of the
state of a barometric pressure at the time of the power-on in a case
where the end is under the state of the normal barometric pressure by
referring to the previous closing information recorded at a time of
starting the operation of the operation control apparatus by the
power-on.

8. An operation control program causing a computer that controls operation
of a magnetic disc device, which is provided with a guarantee range of
assuring reliability of operation with respect to a state of barometric
pressure and has a magnetic disc and a magnetic head for writing and
reading information in and out the magnetic disc while moving over the
magnetic disc without being in contact with the magnetic disc by giving
an instruction to the magnetic disc device, function to record previous
closing information indicative of whether or not the operation end of the
operation control apparatus is done under a state of a normal barometric
pressure within the guarantee range of assuring operation of the magnetic
disc device, and to provide irrespective of the state of a barometric
pressure at the time of the power-on an operation start instruction to
the magnetic disc device in a case of where the end is under the state of
the normal barometric pressure in reference of the previous closing
information, recorded at a time of starting the operation control
apparatus by the power-on.

9. A recording medium having the operation control program according to
claim 8, recorded in it to be readable therefrom.

Description:

FIELD OF THE INVENTION

[0001]The present invention relates to a technique of controlling
operation of a magnetic disk device by instructing to the magnetic disc
device having a magnetic disc and a magnetic head for writing and reading
out information with respect to the magnetic disc while moving the
magnetic head over the magnetic disc without being in contact therewith.

BACKGROUND OF THE INVENTION

[0002]As this kind of the magnetic disc device, there is known a hard disc
drive (hereinafter referred to HDD). A magnetic head of the HDD floats
over a layer of air that is produced by a kinetic pressure of the air
caused by rotation of a magnetic disc, and is set up to read and write
data in a state that the magnetic head is not directly in contact with
the magnetic disc. However, because the HDD is configured to equalize an
outer pressure value and an inner pressure value by means of a vent hole,
the above kinetic pressure caused by barometric pressure (altitude) used
changes and the magnetic head may be in contact with the magnetic disc.

[0003]Therefore, in a normal HDD, reliability is guaranteed in a warrantee
range in which reliability is assured while preventing a magnetic head
from being directly in contact with a magnetic disc on an entire area of
the magnetic disc (barometric pressure generating a kinetic pressure
bearable against impact and vibration caused during operation of the
magnetic disc, for example, 0.6 atm (corresponding to an altitude of
about 4,300 m) and 0.7 atm (corresponding to an altitude of about 3,000
m) when the temperature of HDD is 55 degree C. or more). For example, in
a vehicle, a control device (hereinafter referred to as a vehicle control
device) for controlling fuel injection is equipped in an in-vehicle
navigation apparatus having an HDD equipped on it. For example, it is
possible to stop operation of HDD to thereby protect the HDD in a case
where a barometric pressure shown in barometric pressure information
indicating a barometric pressure outside a vehicle and obtained from the
vehicle control device via a controller-area-network (CAN). Although the
barometric pressure is detected mainly to adjust injection amount of
fuel, the barometric pressure information indicative of the barometric
pressure may be obtained by the in-vehicle navigation apparatus via the
CAN thereby reducing a number of parts composing of a barometric pressure
sensor for detecting independently for the in-vehicle navigation
apparatus.

[0004]In a related art, Patent Document 1, there is disclosed a technique
of protecting an HDD in its entirety by stopping operation of the HDD
under a shutdown state in a case where the HDD detects itself various
environmental conditions of the HDD using various sensors and when
environment specification is violated by eluding from a range of operable
environment

[0005]Meanwhile, it is necessary to read necessary data from an HDD for
starting up various functions of an in-vehicle navigation apparatus by
turning on an ACC power source of the vehicle. For this, it is necessary
to turn on a starting switch for starting a vehicle control switch in
order to obtain barometric pressure information from the vehicle control
device. Accordingly, while the ACC power source is turned on and the
starting switch is not turned on, because the barometric atom pressure is
not obtained, it is impossible to start the HDD. On the other hand, if
the barometric atom pressure is obtained after turning on the staring
switch and the HDD is started, there is a problem that start of the HDD
and start of various functions in the in-vehicle navigation apparatus are
delayed.

[0006]The present invention is made to solve such the problems and to
provide a navigation apparatus, an operation control apparatus, an
operation control method, and an operation control program enabled to
shorten a time from power-on to starting-up of an HDD in a system
determining whether or not the HDD is allowed to start in consideration
of barometric pressure information.

Means for Solving the Problem

[0007]To solve the above problem, according to claim 1 of the present
invention, there is provided an operation control apparatus for
controlling an operation of a magnetic disc device by instructing to a
magnetic disc device having a magnetic disc and a magnetic head for
writing and reading out information with respect to the magnetic disc
while moving above the magnetic disc without contacting the magnetic
disc, the operation control apparatus including: a recording means for
recording previous end information indicative of whether or not end of
the operation in the operation control apparatus by previously turning
off the operation control apparatus, and an operation control means for
giving an operation start instruction with respect to the magnetic disc
device in a case of a normal end, determined at a time of starting
operation of the operation control apparatus by power-on in reference of
the previous end information.

[0008]According to Claim 7 of the present invention, there is provided an
operation control method for controlling operation of a magnetic disc
device by instructing to a magnetic disc device having a magnetic disc
and a magnetic head for writing and reading out information with respect
to the magnetic disc while moving above the magnetic disc without
contacting the magnetic disc, the operation control method including: a
recording step of recording previous end information indicative of
whether or not end of the operation in the operation control apparatus by
previously turning off the operation control apparatus, and an operation
control step of giving an operation start instruction with respect to the
magnetic disc device in a case of a normal end, determined at a time of
starting operation of the operation control apparatus by power-on in
reference of the previous end information.

[0009]According to Claim 8 of the present invention, there is provided an
operation control program causing a computer to function, by providing an
instruction to a magnetic disc device having a magnetic disc and a
magnetic head for writing and reading out information with respect to the
magnetic disc while moving above the magnetic disc without contacting the
magnetic disc, to record previous end information indicative of whether
or not end of the operation in the operation control apparatus by
previously turning off the operation control apparatus, and to give an
operation start instruction with respect to the magnetic disc device in a
case of detecting a normal end by referring to the previous closing
information, recorded at a time of starting the operation control
apparatus by the power-on.

BRIEF DESCRIPTION OF THE DRAWINGS

[0010]FIG. 1 A view for showing aschematic structure of a navigation
apparatus according to an embodiment of the present invention.

[0011]FIG. 2 A flow chart showing an example of a process in a system
control unit 9.

[0024]Hereinafter, embodiments of the present invention will be described
in reference of figures. Here, the embodiments explained below are
embodiments in a case where the present invention is applied to an
in-vehicle Navigation Apparatus equipped in a vehicle.

[0025]First, in reference of FIG. 1, a structure and a function of the
in-vehicle navigation apparatus according to the present embodiment will
be described.

[0026]FIG. 1 is a view showing a schematic structure of the in-vehicle
navigation apparatus according to the present embodiment.

[0027]As shown in FIG. 1, the in-vehicle navigation apparatus S is made up
of a global positioning system (GPS) receiving unit 1, a sensor unit 2, a
communication unit 3, an HDD 4 (an example of magnetic disc device), a
nonvolatile memory 5 (an example of recording means), a display unit 6, a
phonetic output unit 7, an operation unit 8, a system control unit 9 (an
example of operation control unit) or the like, wherein each of the
component parts are mutually connected through a system bus 10 so as to
receive power supply from an ACC power source (not shown).

[0028]The GPS receiving unit 1 receives navigating electric wave outputted
from a GPS satellite through a GPS antenna, measures it based on the
received signal and outputs measured data (longitude, latitude and
altitude information) to the system control unit 9.

[0029]The sensor unit 2 has various sensors for example a speed sensor for
detecting a vehicle speed based on a vehicle speed pulse and outputs
various data detected by these sensors to the system control unit 9.

[0030]The communication unit 3 is connected to an in-vehicle bus (for
example, CAN) 20. It is possible to receive various information from
various sensors and machines which are connected to the in-vehicle bus
20. The received information is outputted to the system control unit 9.
In the present embodiment, barometric pressure information indicative of
barometric pressure detected by a vehicle control apparatus equipped in a
vehicle (a detecting apparatus for detecting a barometric pressure) is
receivable by a communication unit 3 through an in-vehicle bus 20.
Although not shown, HDD 4 is made up of a hard disc (magnetic disc), a
magnetic head, an actuator, a spindle motor, a servo control unit, a
thermo sensor, and a data processing unit or the like. The hard disc has
an information recording area (recording surface) in a ring-like shape
where a large number of data tracks are concentrically arranged. The
information recording area has navigation data and a program (the
operation control program according to the present invention) necessary
for a navigation process. In the navigation process, there are included a
map display process for displaying for example a map around a current
position of the vehicle, a route searching process for searching a most
suitable route to a destination (destination set up by a user), a route
guiding process for guiding the route (for example the most suitable
route) to the destination. Further, the navigation data include for
example map data and various set-up data and so on.

[0031]A hard disc is rotated and activated by a spindle motor. The
actuator has a voice coil motor as a source of driving the actuator and
rotated by the voice coil motor. Further, the servo control unit is
driven and controlled by the spindle motor and the voice coil motor under
a control of the system control unit 9.

[0032]The magnetic head is used to write or read out information to or
from the hard disc. The magnetic head is attached to a tip end of the
actuator to thereby move in a radius direction of the actuator along with
rotation (angular rotation) of the actuator above the hard disc without
contact with the hard disc. Further, the magnetic head is connected to
the data processing unit. Further, the magnetic head is connected to the
data processing unit to thereby enable amplification of the signal
related to information read out by the magnetic head in the data
processing unit, a predetermined decode process and so on. Thereafter,
for example, the signal is outputted to the system control unit 9.
Meanwhile, the signal related to the information to be written on the
hard disc is inputted from for example the system control unit 9 to the
data processing unit. After a predetermined encoding process is carried
out, the signal is written on a predetermined information recording area
(a target track position designated by the system control unit 9) on the
hard disc by the magnetic head. Further, the temperature sensor is
provided inside the HDD 4 to thereby detect a temperature inside the HDD
4.

[0033]The nonvolatile memory 5 is made of for example a Flash EPROM
(Erasable Programmable Read Only Memory) or the like and is possible to
record a previous closing information indicative of whether or not the
operation of the in-vehicle navigation apparatus S normally ends by the
previous cutoff of the ACC power source.

[0034]The display unit 6 is provided with, for example, a depiction
processing unit, a buffer memory, a display and so on. After the
depiction processing unit expands the map data and so on on the buffer
memory and draws an image under a control of the system control unit 9,
the image is displayed on a screen of the display.

[0035]The sound output unit 7 has for example a digital/analogue signal
converter (DAC), an amplifier, a speaker and so on. After the DAC
converts a data under voice related to guidance for driving, outputted
from the system control unit 9, from digital to analogue, the data under
voice are amplified by the amplifier and outputted from the speaker.

[0036]The operation unit 8 has a plurality of instruction buttons
(operation buttons) to accept various instructions from a user and
outputs instruction signals corresponding to the instruction buttons
pushed by the user to the system control unit 9.

[0037]The system control unit 9 has a CPU having a calculating function, a
working RAM, and ROMs for memorizing various data and programs and
totally controls structural elements of the navigation apparatus S. The
system control unit 9 functions as an operation control unit and so on of
the present invention by making the CPU read a program (including
operation control program according to the present invention) recorded on
a hard disc of for example the HDD 4, controls operation of the HDD 4 by
instructing the HDD 4, and simultaneously carries out a navigation
process in use of the navigation data.

[0038]More specifically, the system control unit 9 as an operation control
means refers to the previous closing information recorded in the
nonvolatile memory 5 when the in-vehicle navigation apparatus S starts
its operation (activation) by turning on the ACC power source. In a case
where the in-vehicle navigation apparatus S normally ends, i.e. operation
of the in-vehicle navigation apparatus S normally ends in the previous
turning-off of the ACC power source, the system control unit 9 gives an
instruction of starting operation in the HDD 4. The servo control unit of
the HDD 4 receiving such the instruction of starting the operation makes
the spindle motor start (initiate rotation) thereby starting up the HDD
4. Meanwhile, the system control unit 9 refers to the previous closing
information memorized in the nonvolatile memory 5. When it does not
normally end, barometric pressure information indicative of a barometric
pressure at a present position (barometric pressure information
indicative of a barometric pressure detected by the vehicle control
apparatus) is acquired through an in-vehicle bus 20 and a communication
unit 3. In a case where the barometric pressure indicated by the
barometric pressure information thus acquired is normal, an operation
starting instruction is given to the HDD 4.

[0039]Here, it is determined whether or not the barometric pressure is
normal by whether or not it is for example 0.6 atm (threshold barometric
pressure) or more, namely when it is 0.6 atm or more the normal pressure
is determined. Further, the system control unit 9 may have a structure
such that temperature information indicative of an inner temperature is
acquired from the temperature sensor and it is determined whether or not
the normal barometric temperature exists base on the barometric pressure
information and the temperature information. For example, in a case where
the temperature indicated in the temperature information is the threshold
temperature or more (for example 55 degree C.), the threshold barometric
pressure is raised and it is determined to be the normal pressure in a
case where the barometric pressure indicated in the barometric pressure
information is form example higher than for example 0.7 atm.

[0040]Further, the normal end means a state that it is judged to be for
example a normal barometric pressure and the navigation apparatus S ends
by turning off the ACC power source (a normal barometric pressure at the
previous end time). In a case where a present barometric pressure is a
normal barometric pressure (for example, in a state that it is judged to
be the normal barometric pressure) at a time of ending the operation by
turning off the ACC electric power, the previous closing information
indicative of the end of operation is recorded in the nonvolatile memory
5, and in a case where the present barometric pressure is not the
barometric normal pressure (abnormal barometric pressure) the previous
closing information indicating that the operation has not normally ended
is recorded in the nonvolatile memory 5.

[0041]Further, after the system control unit 9 gives an operation start
instruction to the HDD 4, it acquires the barometric pressure information
indicative of the barometric pressure through the in-vehicle bus 20 and
the communication unit 3 (for example periodical acquisitions). In a case
where the barometric pressure indicated by the barometric pressure
information is not the normal barometric pressure, an instruction of
stopping the operation is given to the HDD 4. The servo control unit of
the HDD 4 which receives such the instruction of stopping the operation
makes the spindle motor stop thereby stopping the HDD 4 to be in a
protected state.

[0042]First, in reference of FIG. 2, an operation of the in-vehicle
navigation apparatus S according to the present embodiment will be
described.

[0043]FIG. 2 is a flow chart showing an example of a process in the system
control unit 9.

[0044]In FIG. 2, when the ACC power source is turned on, operation of the
in-vehicle navigation apparatus S is started by the system control unit 9
(Step 1). At this time, the spindle motor in the HDD 4 is in a stopped
state.

[0045]Next, the system control unit 9 acquires temperature information
indicative of a temperature inside the HDD 4 from a temperature sensor,
simultaneously refers to the previous closing information after reading
out from the nonvolatile memory 5, determines whether or not it is the
normal end (whether or not a flag indicative of the normal end (Step S2).
In a case where it is the normal end (Step S2: YES), the operation
starting instruction is given to the HDD 4 (Step S3). By this the spindle
motor in the HDD 4 starts.

[0046]The system control unit 9 acquires the barometric pressure
information indicative of the barometric pressure from the vehicle
control apparatus through the in-vehicle bus 20 and the communication
unit 3 in a case where the ignition is turned on (Step 4), and judges
whether or not the barometric pressure indicated by the barometric
pressure information thus acquired is the normal barometric pressure
(Step S5). As described above, in a case where it is judged to be the
normal temperature based on the barometric pressure information and the
temperature information, the temperature information acquired in Step 1
is referred to (similar in Step S11).

[0047]In a case of the normal barometric pressure (Step S5: YES), the
operation is continued (Step S6) and the process goes back to Step S5. On
the other hand, in a case of not being the normal barometric pressure
(abnormal barometric pressure out of the assurance) (Step S5: NO), the
system control unit 9 makes the display unit 6 display an alert message
indicative of an abnormal barometric pressure on the display unit 6 (Step
S7), gives the instruction of stopping the operation to the HDD 4 (Step
S8), and goes to Step S10. By this operation stop instruction, the
spindle motor of the HDD 4 stops and the HDD 4 is in the protected state.

[0048]On the other hand, in a case where it is judged to be the abnormal
state in the above step S2 (Step S2: NO), the alarm message indicative of
not being the normal end (abnormal end) is displayed in the display unit
6 (Step S9).

[0049]In the next, the system control unit 9 acquires the barometric
pressure information indicative of the barometric pressure from the
vehicle control apparatus through the in-vehicle bus 20 and the
communication unit 3 when the ignition is turned on (Step S10). It is
judged whether or not the barometric pressure indicated in the barometric
pressure information thus acquired is the normal pressure or not (Step
S11). In a case where it is the normal barometric pressure (Step S11:
YES), the system control unit 9 restarts a restart message on the display
unit 6 (Step S12). Then the process moves to Step S3 and the process
described above is done in a manner similar thereto. On the other hand,
when it is not the normal barometric pressure (Step S11: NO), the system
control unit 9 maintains the operation stopping state of the HDD 4 and
goes back to Step S10, wherein the process is repeated until the normal
pressure is obtained.

[0050]After providing the operation stop instruction to the HDD 4 in Step
S8, in the judgment whether or not it is the normal barometric pressure
carried out in Step S10 through Step S11 after receiving the operation
stop instruction with respect to the HDD 4 in Step S11, it is possible to
construct such that a threshold barometric pressure (a threshold
barometric pressure for reversion) is raised. For example, in a case
where the barometric pressure is higher than 0.71 atm or the barometric
pressure is higher than 0.61 atm and the temperature is less than 50
degree C., it is judged that the normal barometric pressure is reverted.

[0051]Further, in the process of FIG. 2, when there is provided the
instruction of turning off the ACC power source (for example, the user
operates the operation unit 8 to input the instruction of turning off the
AC power source), the system control unit 8 records the previous closing
information indicating that the operation has normally ended in a case
where the barometric pressure indicated by the barometric pressure
information obtained immediately before is a normal barometric pressure.
Meanwhile, in a case where the barometric pressure is not the normal
barometric pressure, the previous closing information indicative of the
operation end is not normal is recorded in the nonvolatile memory 5. Then
the process ends.

[0052]As described above, according to the above embodiment, the previous
closing information recorded in the nonvolatile memory is referred to at
a time of starting operation of the in-vehicle navigation apparatus S by
power-on. In a case of the normal end, the operation stating instruction
is given to the HDD 4, and in case of not being the normal end, the
barometric pressure information indicative of the barometric pressure at
the present position is acquired. Because it is configured such that the
instruction of starting operation is given to the HDD 4, it is possible
to properly protect the HDD 4 while shortening a time from power-on to
start-up of the HDD 4 (escaping from delay of the start-up of various
functions in the in-vehicle navigation apparatus S)

[0053]Next, a countermeasure to the case where the vehicle control
apparatus cannot detect a barometric pressure in the above embodiment
will be described. Further, it is possible to mention for example
vibration, impact, temperature, humidity and condensation as the factor
that the vehicle control apparatus cannot detect the barometric pressure.

[0054]In a case where the vehicle control apparatus cannot detect the
barometric pressure, it is possible to make the barometric pressure
indicative of an identical fixed value (for example, 1 atm (760 mmHg))
being kept outputting from the vehicle control apparatus. For example,
the barometric pressure indicated by the barometric pressure information
thus acquired is changed from an abnormal barometric pressure (for
example, 0.7 atm (532=Hg) or less) to one atm. Thereafter, in a case
where the system control unit 9 recognizes that the one atm is constant,
for example the barometric pressure information indicative of the one atm
is obtained a plurality of consecutive times (five times), it is judged
that the barometric pressure cannot be detected and it is configured that
the barometric pressure cannot be detected and the process under the
abnormal barometric pressure is carried out (for example, continuation of
the protected state of the HDD 4). Meanwhile, for example, in a case
where it is recognized that the normal barometric pressure is suddenly
changed from the normal pressure to one atm and thereafter the system
control unit 9 recognizes a case where the barometric pressure indicated
in the barometric pressure information thus obtained is constantly one
atm (namely, the vehicle control apparatus is in a state that the
barometric pressure cannot be detected) and the barometric pressure
indicated by the barometric pressure information obtained immediately
before the constant one atm, it is configured that the HDD 4 is
continuously operated without giving an instruction of stopping operation
to the HDD 4. According to such the structure, it is possible to properly
deal with a case where the vehicle control apparatus cannot detect the
barometric pressure. Meanwhile, during the barometric pressure
information indicative of one atm is kept being outputted because the
barometric pressure cannot be detected, the ACC power is off and
thereafter the barometric pressure information indicative of the
barometric pressure outputted when the Acc power is on is set up to be
for example a lowest limit value (e.g. 91.4 mmHg), it is judged that to
be not a normal end in Step S2 and is possible to display an alarm
message indicative of not being the normal end can be displayed on the
display unit 6 without giving an operation start instruction to the HDD
4. Without limiting to dealing with the case where the vehicle control
apparatus cannot detect by recognizing the continuous output of the
barometric pressure information indicative of the identical fixed value,
it is also possible to deal with the case where the vehicle control
apparatus cannot detect the barometric pressure in a case where a
variation between the barometric pressure indicated by the barometric
pressure information previously acquired and the barometric pressure
indicated by the barometric pressure information currently acquired is a
predetermined value or more. Namely, provided that the predetermined
value is 0.3 atm, in a case where the barometric pressure indicated in
the barometric pressure information previously acquired is 0.7 atm and
the barometric pressure indicated in the barometric pressure information
currently acquired is 1.0 atm, the variation is 0.3 atm. Then it is
determined the variation is the predetermined value or more and the above
countermeasure for the abnormal barometric pressure can be carried out.

[0055]Meanwhile, in the above embodiment, the normal end is a state that
the navigation apparatus S ends under the normal barometric pressure by
turning off the ACC power. As another example, an altitude may be
detected by the GPS receiving unit 1 instead of using the barometric
pressure and the normal end may be defined as end of the navigation
apparatus S by ACC power-off under a normal altitude (e.g. about 4,300 m
or less (3,000 m or less in an HDD temperature of 55 degree C. or more)).

[0056]Further, in the embodiment, the system control unit 9 is exemplified
as an operation control means of the present invention. However, the
present invention is not limited thereto, and the servo control unit in
the HDD 4 may be configured to function as the operation control unit
according to the present invention. In this case, in a manner similar to
the above system control unit 9, the servo control unit in the HDD 4
refers to the previous closing information recorded in the nonvolatile
memory 5 (which may exist in the HDD 4) at a time of starting the
in-vehicle navigation apparatus S by ACC power-on. In a case where it is
the normal end, the operation start command is given to the HDD 4 (here,
the spindle motor). In case of not being the normal end, the barometric
pressure indicative of the current position is acquired, and when the
barometric pressure is the normal barometric pressure the operation start
command is given to the spindle motor.

[0057]Further, in the embodiment, the example that the present invention
is applied to the navigation apparatus equipped in the vehicle is
exemplified. However, the present invention is not limited thereto. For
example, the present invention can be applied to a communication
navigation apparatus configured by a communication navigation terminal
and a communication center apparatus connected through an antenna and a
mobile communication network (including a radio base station and so on)
to the communication navigation terminal. Further, the present invention
is applicable to other electronic apparatuses equipped in a vehicle and
having an HDD.

[0058]Further, although the navigation apparatus equipped in the vehicle
is exemplified, the present invention is not limited thereto and also
applicable to, for example, a mobile phone, a PHS, a PDA, and so on
having an HDD in it.

[0059]Further, in the embodiment, although it has been explained about a
case where the HDD is used as the magnetic disc, another apparatus having
a magnetic disc and a magnetic head provided to write in and read out
information from and into the magnetic disc while moving over the
magnetic disc without being in contact with the magnetic disc.